How does a waterjet work?

There are two main steps involved in the waterjet cutting process. First, the ultra-high-pressure pump or Electric Servo pump generally pressurises normal tap water pressure levels above 50,000 psi (3450 bar) to produce the energy required for cutting. Second, the water is then focused through a small precious stone orifice to form an intense cutting stream. The stream moves at a velocity of up to 2.5 times the speed of sound, depending on how the water pressure is exerted. The process is applicable to both waters only and abrasive jets. For abrasive cutting applications, abrasive garnet is fed into the abrasive mixing chamber, which is part of the cutting head body, to produce a coherent and an extremely energetic abrasive jet stream.

The waterjet system uses Ultra High Pressure created by the high pressure pump.
The output water is pumped at high pressure to the CNC cutting machine.
The water flow is metered by the cutting head. The Diamond Orifice inside creates a very small diameter jet.

In Water Only applications – the jet directly from the orifice makes the cutting. Typically an Orifice diameter (0.007” / 0.175mm) is used. The jet is concentrated over a very small area and can easily cut though softer materials.

In Abrasive Waterjet applications – after passing the Orifice (typically 0.012” / 0.30mm), the jet then passes through a mixing chamber. This creates a venturi effect which draws in the abrasive. The abrasive clings to the water stream and is directed into the Focus Tube (or Nozzle Tube). A focused Abrasive Waterjet stream emerges which can cut through any material.